Burglar-alarm.



PATENTBD MAR. 24, 1908.

o. LIAGI. BURGLAR ALARM.

/ E T /vl/ /V OR A fr0/emi V5 Jffzl APPLICATION FILED JUNE 6, 1907.

UNITED STATES PATENT OFFICE.

COSMO LIACI, OF NEW HAVEN, CONNECTICUT.

BURGLAR-ALARM.

T6 all whom it may concern:

Beit known that I, CosMo limer, a citizen of the United States, residing at New Haven,

lin the county of New Haven and State of Connecticut, have invented a new and useful Burglar-Alarm, of which the following is a specification. f

IThis invention has reference to improvements in burglar alarms, and its object is to provide an alarm which may be readily applied to windows or doors and may be operated by the opening of the window or door by an unauthorized person, or may be set into operation by an authorized person to give an alarm to notify others of the threatened entrance of burglars or other unauthorized persons.

The invention consists essentially of a contact making device forming the terminals of an electric circuit, which contact making device may be so attached to a door or window that upon the opening of either the electric circuit will be closed until the door or window is shut, and may also be closed by an authorized person such as the occupant of the house or room wherein the contact devices are located so as to remain closed and give a continuous alarm until such authorized person sees fit to break the circuit.

The invention will be fully understood from the following detailed description wherein reference is made to the accompanying drawings forming part of this speciiication, in which,

Figure 1 is a view showing two contact making devices, one located in operative relation to a door and the other to the two sashes of a window, and with the electric circuits shown diagrammatically, Fig. 2 is a side elevation, partly in section, of the contact making device, showing it in one position; Fig. 3 is a front elevation of the device, partly in section, showing another position the contact making device assumes during another phase of the operation; and Fig. 4.

is a perspective view, partly in section, showing parts cooperating with the contact making device.

Referring to the drawings, and moreveseeially to Figs. 2 and 3, there is shwn a base plate 1 upon which are fastened two brackets 2 3 spaced apart and each having one arm 4 projecting away from the base plate 1 facing each other, and in each arm 4 there is a socket 5 to receive a trunnion 6 Specification of Letters Patent.

Application filed June 6, 1907.

Patented March 24, 1908.

Serial No. 377,627.

formed at the free end of each leg 7 7 of a U-shaped frame 8, the structure being such that the U-shaped frame 8 may be turned with relation to the brackets 2 3 upon its trunnions 6 as pivots. If desired, the iit between the trunnions 6 and sockets 5 may be such that there is considerable frictional engagement and the frame 8 will therefore remain in any position to which it may be turned with relation to the brackets 2 3.

Centrally through the body of the frame 8 in a line parallel with the legs 7 thereof is a passage 9, at the inner end of which is formed a countersunk enlargement 10. At each end of the passage 9 there is applied to the corresponding face of the'fiamc 8 annular' contact plates 11 12, made of metal and connected together by a band 13 which may be secured to the frame 8 by a screw 14. The plates 11 and 12 and the band 13 may, if desired, be made of one piece of sheet metal stamped out vand bent into proper shape. The frame 8, or at least that portion immediately contiguous to the passage 9 and the plates 11'and 12 and connecting band 13, should be of insulating material, and in practice it is preferablc'to make thc entire frame of insulating material, although the trunnions 6 may, if desired., be made of metal and attached to the frame in any suitable way.

Extending through the passage 9 is a rod 15 formed at one end into a hook or eye 16 and carrying contiguous thereto an annular plate 17. The other end of the rod 15 receives another plate 18 between which and the bottom of the countersunk enlargement 10 the rod carries a helical spring 19. The rod 15 may be threaded throughout its length, as shown, and the plates 17 and 18 may have nuts formed in them so that they may be screwed upon said rod, or the plate 17 may be fast upon the rod adjacent to the eye 16 and the plate 18 may either be screwed upon the rod or the opening therethrough may be large enough so that this plate 18 will slide on said rod. Applied to the rod adjacent to the plate 18 is a wing nut 20 which may be utilized to adjust the plate 18 on said rod against the action of the spring 19 if the plate 18 is loose on said rod, and this nut 20 will act as a clamp nut for the plate 18 if the latter is made to screw upon said rod. In either instance, the plate 18 or the nut 20 will serve to regulate the tension of the spring 19 and determine the length of travel of the rod 15 through the passage 9 until either the plate 17 abuts against the contact plate 11 or the plate 13 abuts againstthe contact plate 12. The openings in the plates 11 and 12 are of such size. that there can be no contact between the rod 15 or spring 19 and the said plates 11 and 12.

Referring for the moment to Fig. 1, there is there shown a battery 21 or other source of electric current7 and this battery supplies the energy to operate the alarm bell 22 or other 'electrically operated alarm mechanism, and the battery and bell are in circuit through conductors 23-24 with other conductors 25-26 which may branch to the plates 11 and 12 and to the nut 20 respectively, as best indicated in Fig. 3; thus both plates 11 and 12 constitute one terminal. of an alarm circuit and the plates 17 and 1S, which may be brought into contact respectively with the plates 11 and 12, constitute the other terminal of the electric alarm circuit. The alarm circuit may also have interposed therein at any appropriate point a switch 27 yof ordinary construction.

The eye 16 of the rod 15 carries a ring 23 and this ring has attached to it a cord 29, which latter, as shown on the left-hand side of Fig. 1, may carry at its other end a ring 30 to be attached to a door by means of a hook 31; or, this cord 29 may, as shown on the right-hand of Fig. 1, carry at its other end a suction fastening device 32, best shown in Fig. 4. This suction device may be in the shape of a cup of some soft material such as rubber or leather, as indicated in Fig. 4, having a metallic stud 33 at its center, which stud is provided with a ring 34 to which the end of the cord 29 is secured.

The cup of the fastening device 32 may be moistened and pressed against any smooth surface such as a glass window pane or even a varnished door panel, and by being pressed irmly against the same so as to expel the air will be firmly attached to said smooth surface by the surrounding air pressure. 1t will be seen, therefore, that this attaching device 32 is especially adapted for connecting the contact mechanism to the glass panes of the upper and lower sashes of a window, as shown in Fig. 1, and in order that the pull on lowering the upper sash or raising the lower sash may be transmitted in the proper direction through the cord 29 to the contact device, guide roller brackets 35 are attached to the window frame at appropriate places. In order that one contact device may be utilized for both sashes, the cord 29 may be formed of two strands uniting into a single cord before reaching the contact device, as indicated on the right-hand side of Fig. 1. In Fig. 4 there is illustrated a simple form of bracket 35 wherein the upper end of the bracket isformed into a finger 36 bent over so that its outer end covers the outer end of the pintle of a roller 37 and holds the roller in place.

On each frame S there is pivoted an arm 33 to which is pivoted a forked block 39 of insulating material arranged to be moved to a position to straddle the rod 15 and prevent the plate 17 from making contact with the Contact plate 11. This block 39 is movable into and out of the path of the plate 17 by the turning of the arm 38 on its pivot 40 in the frame 8, and a spring 41 fast on the arm 3S tends to hold the block 39 in a position so that it will find its way between the plate 17 and the plate 11 when the arm 33 is moved about its pivot to carry the block 39 toward said plates. To facilitate the introduction of the block between the plates 11 and 17, the free ends of the forked end of the block are beveled,'as indicated at 42, and the edge of the plate 17 toward the block 11 is also beveled or rounded, as indicated. This enables the beveled end 42 of the block 39 to readily enter between the plates 1`1 and 17 and separate them.

Carried by one or more of the cords 29 is a take-up device, illustrated in Fig. 4. This consists of a U-shaped block 43 of wood or other cheap material having its legs 44 each formed of two parallel members between which there is located a sliding block 45 guided by a pin 46, which latter is surrounded by a spring 47 tending to move the block outwardly from between the members of the legs 44. The blocks 45 are each retained in place between the two members of the legs 44 by a screw 43, or other similar device, passing through said leg members and through a slot 49 formed in each block 45.

Passing in line through the members of the legs 44 are perforations 50 for the cord 29 and these perforations are in line with the slots 49 so that the cord 29 may be threaded through both members of both legs 44 and the slots 49 in the blocks 45. The springs 47 carry these blocks 45 outwardly and thereby clamp the cord 29, as indicated in Fig. 4. This device is provided in order to take up slack in the cords 29 since the pressure on said cords caused by the blocks 45 may be relieved by pressing said blocks to compress the springs 47 and the cord may be drawn into a loop 51 between the legs of the block 43 when the blocks 45 may be released and the cord will be locked, the slack being taken up to the eX- tent of the length of the loop 51. By this device for taking up the slack the cords may be used without change for application to various doors or windows and the amount of slack desired may be readily regulated. Now, suppose that the conditions are such as represented in Fig.- 1 and some unauthorized person attempts to enter by the door or attempts to enter by raising or lowering the respective sashes of the window. The cords are pulled and the plate 13 is brought into contact with the plate 12, as indicated in dotted lines in Fig. 2. This will close the electric circuit and the bell will give an alarm` This operation will take place whether the door be opened or whether one or the other of the window sashes be moved from the closed position. However, should the occupant of the room or house discover that an intruder was attempting to enter through either the door or the window, he may give an alarm by moving the block 39 from between the plates 11 and 17 when the spring 19 will bring the plate .17 into contact with the plate 11, as indicated in dotted lines in Fig. 3, thus closing the electric circuit, and the alarm will be given and the bell will continue to ring so long as the plates 11 and 17 remain in contact. For this purpose it will, of course, be understood that it is desirable to always have a little slack in the cords 29 but this slack should never be sufficient to enable an unauthorized intruder to open the door or window sash to a sul'licient extent to reach and cut the cord before the circuit is closed and the alarm given, and for this reason the take-up device shown in Fig. 4 is an important and useful adjunct to the alarm mechanism herein shown and described.

While I have described the invention as a burglar alarm, it is evident that by the inclusion of a suitable thermostatic device which will normally hold the contacts apart, the invention is equally useful as a fire alarm; or it may be used to transmit tire or burglar alarms to some point exterior to the building in which it is located by placing the signal or bell 22 at the distant point.

I claim:-

1. A burglar alarm comprising an electric circuit, a movable spring-controlled contact device included in said circuit, connections between the same and the point to be protected for actuating the contacts against the action of the spring to close the circuit, other contacts operated by the spring for closing the circuit, and a removable insulating retaining device introduceable between the spring-actuated contacts.

2. A burglar alarm contact device comprising a supporting frame, a conducting rod carried thereby and provided with contact plates on each side of said frame, other contact plates carried by said frame in operative relation to the contact plates on the rod, the contact plates on the frame being arranged to constitute one terminal of an electric cir-. cuit and the contact plates on the rod being arranged to constitute the other terminal of the electric circuit, means for maintaining the circuit normally open at the contact plates, and means Afor closing the circuit at said contact plates.

3. In a burglar alarm, a supporting frame, a spring-actuated conducting rod carried thereby and extending therethrough, connected contact plates on each side of said frame and arranged to constitute one terminal of an electric circuit, other contact plates carried by said rod and arranged to constitute the other terminal of the electric circuit and to make contact with the plates on the frame, and an insulating stop member introduceable between one of the Contact plates on the rod and the corresponding contact plate on the frame.

4. In a burglar alarm, a frame, a conducting rod extending therethrough, conducting plates on each side of said frame and surrounding but out of contact with said rod, contact plates carried by said rod on each side of said frame, a spring on said rod between one of the contact plates and the frame, a nut carried by said rod and engaging the contact plate adjacent to said spring, and means for moving the rod and contact plates against the action of the spring.

5. In a burglar alarm, a frame, a conducting rod' extending through and beyond the same, connected contact plates on each side of said frame and surrounding said rod, other contact plates on said rod on each side of said frame and in operative relation to the contact plates on the latter, a spring surrounding the rod between the frame and one of said contact plates, and an insulating block introduceable between the other contact plate on the rod and corresponding contact plate on the frame.

6. In a burglar alarm` a pivotally supported frame, a conducting rod extending through and beyond said-frame, connected contact lates on each side of said frame and surrounding said rod, contact plates carried by said rod and arranged to make contact with the plates on the frame, a spring interposed between the frame and one of said contact plates, and means Vfor holding the other of said contact plates out of contact with the plate on the block, comprising a pivoted arm carried by said frame, a forked block with beveled ends movable into the path of the last-named contact plate on the rod, and a spring between said arm and said block.

In testimony that I claim the foregoing as my own, I have hereto affixed my signature in the presence of two witnesses.

COSMO LIACI. Witnesses:

ARTHUR J. RosnNBLUTn, PASQUALE RoeozZINo 

